html{
    height: 100%;
}
body{
    background: url('img/4.jpg') no-repeat center/cover;
}
.form{
    width: 500px;
    height: 600px;
    margin: 30px auto;
}
.form_register,.form_login{
    width: 500px;
    background-color:aqua;
    border-radius: 5px;
    box-shadow: 0 0 3px #ccc;  
    overflow: hidden;
    transition: height 1s;
}
.form_register{
    height: 548px;
}

.form form{
   padding: 25px 40px;
}
.form .form_item{
    display: flex;
    margin: 25px 0;
    vertical-align: middle;
}
.form input{
    outline: none;
    text-indent: 10px;
    flex: 1;
    width: auto;
    border: none;
    border-radius: 3px;
    height: 36px;
}
.form form label{
    width: 90px;
    float: left;
    line-height: 36px;
}
h1{
    text-align: center;
    padding: 0;;
    margin: 30px 0 30px 0;
}
.form form input[type='submit']{
    background-color: rgba(244, 22, 7, 0.7);
    color: aliceblue;
    height: 45px;
    font-size: 20px;
    cursor:pointer;
    margin-top: 20px;
}
.form .info{
    text-align: center;
    font-size: 14px;
    margin-bottom: 20px;
}
.form .info span{
    color: crimson;
    margin-left: 3px;
}
.form .info span:hover{
    cursor: pointer;
    border-bottom: 1px solid crimson;
    
}

